Field of the Invention
The present invention relates to a device for packaging and dispensing fluid, liquid or pasty products and, more particularly, to an airless device (device without an air intake) with an extension tip.
In certain fields of use of bottles that dispense fluid products, notably that of pharmaceutical and cosmetic products, it is absolutely essential to ensure that products contained in the bottle are packaged and dispensed without contact with the air. Known devices generally comprise a rigid-shell container in which there moves a piston that drives the product towards the intake orifice in the metering chamber and isolates it from the air entering underneath the piston.
Devices with a rigid container in which there is placed a deformable flexible bag that contracts as the product is gradually extracted from it are also known. The product remaining inside the bag is kept away from the air, while the product may be expelled from the bag by means of an airless pump (with no air intake) or under the pressure of a propellant gas acting on the wall of the bag, inside the bottle.
Moreover, the principle of operation of metering pumps for dispensing fluid, liquid or pasty products is well known. A manual metering pump is generally mounted on a bottle containing the product to be dispensed and consists of a metering chamber of determined volume, of a piston capable of moving in the chamber under the action of a push-button and of at least two valves. The lower valve, or inlet valve, situated at the entrance to the chamber and controlling communication with the inside of the bottle, is closed when the push-button is depressed whereas the upper valve, at the outlet of the chamber, is open, allowing the product expelled from the chamber by the movement of the piston to pass, and then when the push-button is released, the piston rises up inside the chamber under the action of a spring, the upper valve closes again while the lower valve opens, allowing the chamber to fill ready to dispense a further dose of product.
Description of Related Art
A device for packaging and dispensing fluid, liquid or pasty products which is provided with an extension tip is described in patent document FR 2 743 544. This specific tip, which may potentially be provided with a spray nozzle, is positioned at the outlet of the pump, so as to extend the product outlet nozzle.
Such an extension tip may be mounted on a product dispensing device that dispenses a product that is not very sensitive to degradation and is dispensed in relatively imprecise quantities, but is not suitable for a product liable to degrade upon contact with the air and intended to be dispensed in constant individual doses.
This is because such an extension presents technical problems of the risk of contamination of the product contained in the extension tip and of loss of product in the extension tip by outflow, evaporation or capillarity, between two uses, leading to the risk of corrupting the size of dose delivered by the pump.
Another difficulty encountered in the field of pharmaceutical and hygiene products stems from the need to deliver the product to a zone that is not very accessible, such as, for example, the auditory canal of the ear, the sublingual zone, or the lower regions of the body.
A fluid-product packaging and dispensing device provided with an extension tip is also described in patent document FR 2 860 768.
This fluid-product dispenser is provided with a core, connected by a first end to a nozzle associated with a pump mounted on a bottle containing the product that is to be dispensed and that at its distal second end comprises a discharge orifice.
This core bears a jacket of which a first end is arranged on the discharge orifice. This jacket is intended to open at its distal second end that bears a self-closing slot, under the pressure of the product when said pump is actuated.
The jacket comprises a tubular external part that is elastically deformable in longitudinal bending in the manner of a flexible spatula of which a first end is arranged on the discharge orifice and of which the tapering external cross section diminishes evenly towards its distal second end, at least over part of its length.
The use of a simple self-closing slot leads to insufficient closure which is detrimental to the use of this device with products highly sensitive to degradation upon contact with the air and obtaining dispensing in constant unit doses.
In addition, the use of a shutter of flexible spatula type makes the flexibility of the tip limited, and this is detrimental to the delivery of product to a somewhat inaccessible zone.